Do NOT say the D in these 105 Common Words! Part 1

The video tutorial explains how Americans often drop T's and D's in common words to achieve smoothness in speech. It provides examples like 'tens' and 'friendship' where the D is dropped, and discusses the pattern of dropping D in ND consonant clusters. The tutorial also covers how D is dropped when linking words, such as 'friend was', and demonstrates the natural sound of dropped D in full sentences.

What are some examples of phrases where Americans drop the D sound?

Why is dropping the D considered to contribute to the smoothness of American English?